所有的机器上都要安装hadoop，现在就先在Master服务器安装，然后其他服务器按照步骤重复进行即可。
1.首先是上传文件并解压缩。
2.然后是配置Hadoop的环境变量：
3.配置完之后source profile,使更改有效。在app目录下创建几个Hadoop需要用到的文件夹
mkdir /home/wangkai/app/tmp
mkdir /home/wangkai/app/var
mkdir /home/wangkai/app/dfs
mkdir /home/wangkai/app/name
mkdir /home/wangkai/app/data
4.修改hadoop-env.sh文件
5.修改里面的JAVA_HOME路径和HADOOP_CONF_DIR路径
6.配置core-site.xml文件
<configuration>
<property>
<name>hadoop.tmp.dir</name>
<value>/home/wangkai/app/tmp</value>
<description>Abase for other temporary directories</description>
</property>
<property>
<name>fs.default.name</name>
<value>hdfs://192.168.59.131:9000</value>
</property>
</configuration>
7.配置hdfs-site.xml文件
<configuration>
<property>
<name>dfs.name.dir</name>
<value>/home/wangkai/app/dfs/name</value>
<description>Path on the local filesystem where theNameNode stores the namespace and transactions logs persistently.</description>
</property>
<property>
<name>dfs.data.dir</name>
<value>/home/wangkai/app/dfs/data</value>
<description>Comma separated list of paths on the localfilesystem of a DataNode where it should store its blocks.</description>
</property>
<property>
<name>dfs.replication</name>
<value>1</value>
</property>
<property>
<name>dfs.permissions</name>
<value>false</value>
<description>need not permissions</description>
</property>
</configuration>
8.新建并且修改mapred-simt.xml,在该版本中，有一个名为mapred-site.xml.template的文件，复制该文件，然后改名为mapred-site.xml 命令是： cp /home/wangkai/app/hadoop-2.7.3/etc/hadoop/mapred-site.xml.template /home/wangkai/app/hadoop-2.7.3/etc/hadoop/mapred-site.xml
配置mapred-site.xml
<configuration>
<property>
<name>mapred.job.tracker</name>
<value>http://192.168.59.131:9001</value>
</property>
<property>
<name>mapred.local.dir</name>
<value>/home/wangkai/app/var</value>
</property>
<property>
<name>mapreduce.framework.name</name>
<value>yarn</value>
</property>
</configuration>
9.配置yarn-site.xml
<configuration>
<!-- Site specific YARN configuration properties -->
<property>
<name>yarn.resourcemanager.hostname</name>
<value>192.168.59.131</value>
</property>
<property>
<description>The address of the applications manager interface in the RM.</description>
<name>yarn.resourcemanager.address</name>
<value>${yarn.resourcemanager.hostname}:8032</value>
</property>
<property>
<description>The address of the scheduler interface.</description>
<name>yarn.resourcemanager.scheduler.address</name>
<value>${yarn.resourcemanager.hostname}:8030</value>
</property>
<property>
<description>The http address of the RM web application.</description>
<name>yarn.resourcemanager.webapp.address</name>
<value>${yarn.resourcemanager.hostname}:8088</value>
</property>
<property>
<description>The https adddress of the RM web application.</description>
<name>yarn.resourcemanager.webapp.https.address</name>
<value>${yarn.resourcemanager.hostname}:8090</value>
</property>
<property>
<name>yarn.resourcemanager.resource-tracker.address</name>
<value>${yarn.resourcemanager.hostname}:8031</value>
</property>
<property>
<description>The address of the RM admin interface.</description>
<name>yarn.resourcemanager.admin.address</name>
<value>${yarn.resourcemanager.hostname}:8033</value>
</property>
<property>
<name>yarn.nodemanager.aux-services</name>
<value>mapreduce_shuffle</value>
</property>
<property>
<name>yarn.scheduler.maximum-allocation-mb</name>
<value>2048</value>
<discription>每个节点可用内存,单位MB,默认8182MB</discription>
</property>
<property>
<name>yarn.nodemanager.vmem-pmem-ratio</name>
<value>2.1</value>
</property>
<property>
<name>yarn.nodemanager.resource.memory-mb</name>
<value>2048</value>
</property>
<property>
<name>yarn.nodemanager.vmem-check-enabled</name>
<value>false</value>
</property>
</configuration>
10.配置slaves中从机的ip
192.168.59.132
11.启动Hadoop，在namenode上执行初始化
进入到master这台机器的/home/wangkai/app/hadoop-2.7.3/bin目录下，执行./hadoop namenode -format
格式化成功之后，可以在/home/wangkai/app/dfs/name/目录多了一个current目录，而且该目录内有一系列文件
然后进入/home/wangkai/app/hadoop-2.7.3/sbin目录下，执行./start-all.sh启动Hadoop，一路yes下去
12.测试Hadoop
首先是执行命令，关闭防火墙，在centos7下是： systemctl stop firewalld.service
然后是访问master主机 http://192.168.59.131:50070/
自动跳转到了overview页面
在本地输入http://192.168.59.131:8088/
自动跳转到了cluster页面
说明Hadoop配置成功了。
